1. Field of the Invention
This invention relates to a distance indicating mechanism for a lens barrel.
2. Description of the Prior Art
Lens assemblies with autofocusing mechanisms which have been previously known have a fixed outer tube mounted on the camera body and a focusing ring which is accommodated in the fixed outer tube and which moves in the axial direction when turned by a motor, thereby forming a construction in which a distance scale mark positioned in the outer peripheral surface of the focusing ring appears in an indication window formed in a peripheral wall of the fixed outer tube. Since, in the distance scale indicating construction of this type of autofocusing lens assembly, the distance scale is formed on the outer periphery of the focusing ring, it is necessary to increase the dimension of the indication window in the axial direction of the fixed outer tube so that any scale mark will appear in the indication window even when the scale moves to a great extent with the movement of the focusing ring.
In the conventional autofocusing lens assembly having this type of distance scale indicating construction, it is not easy to read the distance scale because it moves in the axial direction below the indication window. Moreover, there is a possibility of a component part such as a glass part mounted in the indication window being damaged or of the mechanical stiffness of the fixed outer tube being reduced as a result of the size of the indication window being excessively large compared with that of the focusing ring.